GA - Representation

In this GA, we assume that repair order can be done by one or multiple technicians.


For repair order that have multiple technicians, the order will be divided into multiple parts based on the number of technician it needs. For example, repair order 10004 will be divided to 10004(A), 10004(B), 10004(C).

Therefore a chromosome is built from genes corresponding to every repair order or it's parts. In our example, a single chromosome consists of 8 genes and completely describes a possible solution to the problem. Each gene consist of two parts. The first part will have value of sequence number of the order and the second part will have value of technician's ID that will execute the order.


However, considering that not all technician can repair all type of breakdown nor all machine, technicians will be divided into several groups. Therefore, every repair order must define which group(s) can execute it.
In this paper, we divide technicians into two groups which are electrical and mechanical. In chromosome representation, repair orders that need electrical technician and repair orders that need mechanical technician are separated. Each repair order has group(s) assigned either electrical or mechanical or both. If both is chosen, system will choose group randomly.

In our example above, we assume
10000 - electrical
10001 - mechanical
10002 - mechanical
10003 - electrical
10004 - both

and for 10004, we assume that the system randomly chose
10004(A) - mechanical
10004(B) - electrical
10004(C) -mechanical